Agitator means for drink mixers



Dec. 18, 1962 M. PATTEN AGITATOR MEANS FOR DRINK MIXERS Filed Feb. 6,1959 FIG.2

FIG.I

INVENTOR. LEIGH M. PATTEN BY ATTORN EYS United States Patent Ofiiice3,059,144 Patented Dec. 18, 1962 3,669,144 AGITATOR MEANS FOR DRINKMIXERS Leigh M. Patten, Seattle, Wash, assignor to Sweden FreezerManufacturing Co., Seattle, Wasln, a corporation of Washington FiledFeb. 6, 195%, Ser. No. 791,662 3 Claims. (Cl. 259-134) The presentinvention relates to an improved agitator for drink mixers of the typeprovided with a relatively long slender mixer shaft adapted to dependfrom a drive motor into the material to be mixed and. having one or morerigid agitator discs or blades secured thereto.

My invention is particularly concerned with the blending of frozenmilkshake product with flavoring syrup and aims to provide an effectiveagitator of simple and economical construction which has substantiallyno tendency to splash even if the finished milkshake is lowered awayfrom the agitator or product is added while the mixer is operating.

Another object of the invention is to provide an agitator which isunusually safe to use.

.A further object is to provide an agitator which will thoroughly mix adrink from top to bottom.

Other and more particular objects and advantages will, with theforegoing, appear and be understood in the course of the followingdescription and claims.

In the accompanying drawings:

FIG. 1 is an elevational view partly in vertical section of my agitator.

FIG. 2 is an end view of the agitator taken as indicated by the line 22of FIG. 1,

FIG. 3 is a fragmentary elevational view partly in vertical section ofthe lower endportion of a modified agitator construction,

FIG. 4 is a side elevational view illustrating my agitator in operationin a drink shown in vertical section, and

FIG. 5 is a detail fragmentary view showing generally the operation ofthe agitator as a drink is lowered away therefrom.

Referring now particularly to the drawings in which like numeralsindicate like parts throughout the several views, the numeral designatesa rotatable mixer shaft of the type here under consideration, and namelyone depending from a drive relation with an electric motor. This shaft10 is centrally tapped at its lower end to receive a shaft extension,and more particularly the threaded upper end portion 11a of a steelinsert 11. It will be noted that the lower end portion 11b of thisinsert is spirally knurled to snugly interfit with the inner wall of ahollow plastic sleeve 12 forced thereover. This sleeve has a terminalagitator button 13 at its lower end formed as an integral part thereof.A11 intermediate agitator button 14 is positioned at the upper end ofthe sleeve and may be integral therewith or be a separate part as shownwhich is sleeved by a central opennig onto the portion 11a of the insertso as to be locked between the lower end of the shaft 10 and the upperend of the sleeve 12.

Other than for the center portion of button 14, both of the agitatorbuttons 1314 are identical concavo-convex discs of a general unbrellashape having constant thickness. Each is curved gently downward throughmost of its radial span by a radius of curvature which may be equal toapproximately three times the rim diameter of the disc, and then bendson a relatively short radius for nearly ninety degrees to form downturned rim skirts 13a14a. The rim edges are intentionally rounded sothat no potentially dangerous sharp edges will be present.

It will be noted that the concave face of the lower agitator button 14is modified by a generally cylindrical center knob 15 formed integrallytherewith. This knob is rounded slightly at its lower edge and does notextend downwardly as far as the level of the rim edge of the button. Itsdiameter is approximately equal to the outside diameter of the sleeve12.

The agitator buttons 1314 are also formed with vent holes 16 which arepreferably located closely adjacent the sleeve 12 and knob 15,respectively. Before discussing the function of these vent holes,attention is directed to FIGURE 4 which is intended to illustrate thatthe upper convex face of the agitator buttons causes the material 17being mixed in the cup 18 to have a downward component as it spinsthereofi. This assures that there will be adequate up and downcirculation of the material. Also, it means that the cup can be filledwhile the mixer is operating therein without danger of splashing theadded material out of the cup should it contact the upper agitatorbutton. For example, to be more specific, frozen milkshake product canbe dispensed into the cup for mixing with flavoring therein while themixer is operating. This results in the saving of time for the operatorand more thorough blending.

Continuing to the functions of the vent holes 16 and knob 15, attentionis directed to FIG. 5 which is intended to illustrate the cup 18 beingwithdrawn from the mixer while it is still operating and in an oifcenterposition, the illustrated critical point being just as the bottomagitator button is breaking clear of the mixed material 17. This is thepoint at which conventional drink mixing agitators would normally splashand throw material out of the cup. In the case of my agitator, althoughthe convex upper face of the buttons deters splashing I have noted thatthe rapid speed of the mixer creates a suction beneath the buttonswhich, were it not for the vent holes, would draw material from the cupif the but-tons were to leave the normal upper level of the materialwhile the mixer was running. This material under suction would then spinfree from the underside of the related agitator button and likely bethrown out of the cup. However, the vent holes break the suction beforethe corresponding button leaves the mixed material proper. In thisregard, I have also found that the vent holes in the bottom agitatorbutton will not necessarily insure that the suction will be broken. Forthis reason I provide the knob 15 which insures a material free zone 20surrounding the upper end of the knob so that air is free to pass inthrough the vent holes and break the suction beneath the button.Experiments have shown that this result is not always attained if theknob 15 is substantially rounded in vertical cross-section.

FIGURE 5 illustrates a modified arrangement wherein the shaft extensionis made by a one-piece metal rod 21 instead of the two-piece plastic andmetal construction hereinbefore described. 'This rod 21 is tapped at itslower end to receive a screw 22 which has a head of the same generalshape as the knob 15. With this arrangement the agitator button 13 canalso perform as a bottom button, the function of the knob 15 beingassumed by the head of the screw 22 used to hold the button on the rod21.

The advantages of the invention, it is thought, will have been clearlyunderstood from the foregoing detailed description of the illustratedpreferred embodiment. Minor changes will suggest themselves and may bere sorted to without departing from the spirit of the invention,wherefore it is my intention that no limitations be implied and that thehereto annexed claims be given a scope fully commensurate with thebroadest interpretation to which the employed language admits.

What I claim is:

1. In combination, a depending mixer shaft having a knob at the lowerend thereof, and an umbrella-like circular agitator button having aconcavo-convex cross-sectional configuration concentrically secured tosaid shaft above said knob and skirting the latter, the portion of saidbutton lying immediately adjacent the knob being pierced bycircumferentially spaced apart vent openings, the upper surface of theagitator button sloping downwardly throughout its entire radial extent.

2. In combination, a depending mixer shaft having a knob at the lowerend thereof, and an umbrella-like circular agitator button having aconcavo-convex cross-sectional configuration concentrically secured tosaid shaft above said knob and skirting the latter, the portion of saidbutton lying immediately adjacent the knob being pierced bycircumferentially spaced apart vent openings, the skirting rim of saidbutton occupying a horizontal plane spaced below the underside of theknob so that, as the mixer and an open-top container for a body ofliquid being mixed are moved vertically relative to one another incourse of Withdrawing the mixer from the liquid, the knob will clear theliquid in advance of said rim. 1

3. In combination, a depending mixer shaft having a knob at the lowerend thereof, and an umbrella-like circular agitator button having aconcavo-convex cross-sectional configuration concentrically secured tosaid shaft above said knob and skirting the latter, the portion of saidbutton lying immediately adjacent the knob being pierced bycircumferentially spaced apart vent openings, said knob being circularand concentrically placed, the knob and the underside of the buttonbeing so formed as to produce a substantially material-free zonesurrounding the knob at its juncture with the .button, the vent holesbeing placed so as to occur within this zone.

References Cited in the file of this patent UNITED STATES PATENTS913,621 Cooper Feb. 23, 1909 1,650,256 Beach Nov. 22, 1927 1,655,447Wait Jan. 10, 1928 1,698,363 Gilbert Jan. 8, 1929 2,190,896 UnderwoodFeb. 20, 1940 2,222,601 Blish et al Nov. 26, 1940 2,548,442 Myers Apr.10, 1951 2,637,537 Ernest May 5, 1953 2,964,301 Bosse Dec. 13, 1960FOREIGN PATENTS 277,605 Switzerland Dec. 1, 1951

